©Journal of Sports Science and Medicine (2013) 12, 323-331
http://www.jssm.org
Research article
The Effects of Scaling Tennis Equipment on the Forehand Groundstroke
Performance of Children
Emma J. Larson 1 and Joshua D. Guggenheimer 2
1
2
Choice Health and Fitness, Tennis Professional, Grand Forks, ND, USA
Department of Physical Education, Exercise Science and Wellness, University of North Dakota, USA
Abstract
The modifications that have taken place within youth sports
have made games, such as basketball, soccer, or tennis, easier
for children to play. The purpose of this study was to determine
the effects low compression (LC) tennis balls and scaled tennis
courts had on the forehand groundstroke performance of children. The forehand groundstroke performances of eight subjects’ (8.10 ± 0.74 yrs) using LC tennis balls were measured on
a scaled tennis court and standard compression balls (SC) on a
standard court. Forehand groundstroke performance was assessed by the ForeGround test which measures Velocity Precision Success Index (VPS) and Velocity Precision Index (VP).
Participants attempted three different forehand rally patterns on
two successive days, using LC balls on the 18.3m court one day
and SC balls on the 23.8m court the other. When using LC balls,
participants’ recorded higher overall VPS performance scores (p
< 0.001) for each non-error stroke as well as higher VP scores (p
= 0.01). The results of this study confirmed that the use of modified balls and modified court size may increase the control,
velocity and overall success rate of the tennis forehand groundstroke of children.
Key words: Performance assessment, velocity, precision, success, compression.
Introduction
In recent years, the game of tennis has seen equipment
modifications emulate the growth and physical development of children, which is similar to other sports scaling
the field, baseball diamond, or gymnasium to the young
athlete (Benham, 1988; Martens et al., 1984; Pang and
Ha, 2005). However, little research has been conducted to
provide evidence of the benefits of using LC tennis balls.
Only two experimental studies (Farrow and Reid, 2010;
Hammond and Smith, 2006) pertaining directly to the
modification of tennis balls and courts could be found
during a current review of the literature. Hammond and
Smith (2006) assessed the transfer of learning that took
place with the use of LC tennis balls compared to standard-compression (SC) balls over the course of 8 weeks,
and found no significant impact on skill development due
to the use of LC balls. The authors used 14 participants
aged 5 to 11 years old. Both the participants’ ages as well
as the number of participants were factors that may have
limited the validity of the researcher’s findings.
Whereas Hammond and Smith (2006) produced
inconclusive results, Farrow and Reid (2010) observed a
significant difference in beginner tennis players’ skill
acquisition on the standard court with the SC ball when
compared to skill acquisition on the scaled court with a
LC ball. Throughout the experiment 8-year-old children’s
skill acquisition was recorded over a 5-week period using
a rally design. The combined court modification, along
with the use of LC balls, allowed for more opportunities
for the children to rally within the lesson. The children
studied also hit more LC balls into the court, had more
fun – as measured by the Steen Happiness Index – and
were more successful with the modified court and balls
(Farrow and Reid, 2010). Considering the previous work
done, one might argue that Hammond and Smith (2006)
initiated the examination of the influence of LC tennis
balls on improving skill development, whereas Farrow
and Reid (2010) continued that line of research, examining specific effects of modified balls and courts on skill
acquisition and physiological responses of children 10
and under.
Despite the previous work which has focused on
the influence of equipment modification on skill development (Farrow and Reid, 2010; Hammond and Smith,
2006), such approaches still need to be refined to incorporate a more comprehensive game approach. Our research
differs significantly from that conducted previously in
that it observes a child’s forehand groundstroke performance during two different scenarios: a standard ball and
court condition and a modified ball and court condition.
Performance testing in the field of tennis appears to be
slowly evolving from what was exclusively skill-based
testing to what we see now: a more dynamic rally-based
performance test.
Thus far, few tennis-specific performance tests
have been available and readily used for testing an athlete’s performance. Up until the late 1960’s the major
disadvantage of performance assessments was that skill
based tests did not simulate the true environment of a
tennis match (Hewitt, 1966; Kemp and Vincent, 1968;
Purcell, 1981; Vergauwen et al., 1998). The KempVincent Rally test was the first of its kind to include a
game-based approach through a rally-based design where
two people are dynamically exchanging the ball back and
forth over the net (Kemp and Vincent, 1968). Speed, or
stroke firmness, was an added variable measured along
with ball control in an attempt to better simulate real
game situations (Purcell, 1981). As technology advanced,
so did the capabilities of quantifying ball speed and
placement within the dynamic environment of a tennis
match. Vergauwen et al. (1998) quantified the precision
and velocity of each tennis ball hit, by using video images
Received: 22 August 2012 / Accepted: 10 January 2013 / Available online: 29 April 2013 / Published: 01 June 2013
324
and a radar system in what they dubbed the Leuven Tennis Performance Test.
Follow-up work led Vergauwen et al. (2004) to
develop what is now known as the ForeGround test,
which has been shown to be both reliable and valid when
assessing the performance of young, low-to-intermediate
level tennis players. The forehand groundstroke is used in
the rally based design of the ForeGround test to assess
performance because of its dominance above other
strokes in a given rally (Elliott et al., 2009; Vergauwen et
al., 2004). Researchers have found that more advanced
players scored higher on the ForeGround test in all of the
tested variables, including speed, accuracy, and success
(Vergauwen et al., 2004). Despite the ForeGround protocol’s attempt to quantify the rally-based performance of
the forehand groundstroke, the application of the test to
tennis as a whole is limited in that it utilizes only one of
the fundamental strokes (service, forehand, backhand and
volley) used for low-intermediate players (Crespo, 2008).
Although previous research has paved the way to performance testing using modified court sizes and ball
types, there appears to be little data available that compares performance when using modified balls and court
relative to performance using standard balls and court.
The modifications that have been made to equipment have slowed the speed of the game, which has made
it easier for children to be successful and learn the skills
required to play effectively (Farrow and Reid, 2010; ITF,
2009). Previously conducted research using adults supports the notion that the ball size and type used within
tennis influences the speed of play (Cooke and Davey,
2004; Haake et al., 2000; Mehta and Pallis, 2001). When
the ball speed is slowed, the player has more time to react
to the movement, direction, and spin of the ball. The benefit of having a larger ball to slow the pace of the game
has been revealed previously in an adult population (Andrew, 2003). Considering the previous literature indicating the use of larger balls in order to slow down the game
of tennis, it seems plausible that similar effects might be
seen when children use lighter, LC balls. Intuitively, children should not play with balls that bounce high above
their typical groundstroke impact zone or travel too fast,
as it may be detrimental to the biomechanical development of their strokes (Barrell, 2008). LC tennis balls thus
have great potential for the training of young tennis players, as the rebound height is much less pronounced; however, there is minimal research indicating the specific
benefits that LC balls may elicit on tennis performance.
Considering the fact that a child’s response time to
a particular stimulus is generally greater earlier on in
childhood (Haywood and Getchell, 2009; Kiselev et al.,
2009) it typically takes them longer to respond. Therefore,
it is important that the speed of sports slows down in
order to meet the physical limitations of the children playing them. Because of their slow motor response time,
children often have difficulties playing the fast-moving
game of tennis. The skills necessary to play the game,
such as executing a serve, returning a serve, and hitting
groundstrokes back and forth over the net in a dynamic
rally setting, are difficult for beginning children, especially if ball or court modifications are not made. Most
Scaling tennis equipment for children
children that are coached in tennis on a standard court
using SC balls are limited to learning skills rather than the
actual game (Anderson et al., 2009). The 11.0m and
18.3m scaled courts diminish the court area to a size appropriate to capabilities of the children playing. With the
modified court there is less area to cover, and correspondingly a child is able to move to more balls and in turn,
keep the rally going longer; the modified court theoretically increases the overall opportunity for children’s rally
success (Farrow and Reid, 2010; ITF, 2009; Newman,
2010). The scaled courts are also proportionate to the
height of the child and therefore to the child’s physical
development. As children develop and their speed and
coordination increases, they should be able to make transitions to larger court sizes and higher compression tennis
balls. Despite this intuitive transition to modified equipment, there is still a lack of quantitative evidence for the
application of LC tennis balls. Therefore, the purpose of
this study was to determine the effects of modifying court
size and ball type on the forehand groundstroke performance of children. It was hypothesized that children would
score higher on the ForeGround test using modified
equipment and modified court conditions when compared
to the use of standard equipment and standard court conditions, indicating a higher forehand groundstroke performance with the use of modified equipment.
Methods
Participants
Eight tennis players (five girls and three boys) between
the ages of 7 and 9 (8.10 ± .74 yrs) were recruited to participate in this study. Each of the participants had tennis
playing experience (2.50 ± 1.21yrs) and was enrolled in
tennis programming at the time of data collection in order
to ensure that each of them was capable of completing the
ForeGround test explained in detail below. Participant’s
tennis programming prior to the research provided them
with exposure to both orange and yellow courts. The
parents of each participant signed a voluntary consent
form and provided demographic data about their child.
Approval to conduct this study was granted by the Institutional Review Board of the University of North Dakota.
Participants were selected based upon age-specific guidelines from ITF’s Tennis 10’s manual, which recommends
that children between the ages of 5 and 10 play on a
scaled court (ITF, 2009). Participants in this study had
been exposed to and were assessed on both the yellow and
orange courts due to the lack of age-based specificity in
tennis programming. As boys and girls differ little in
height at that age, (Barrell, 2008) there was no need to be
sex exclusive in participant selection.
Performance measures
In order to assess participant forehand groundstroke performance, the ForeGround test was utilized, to calculate
both the velocity-precision-success (VPS) score and the
velocity-precision (VP) score (Vergauwen et al., 2004).
These two dependent variables were the main indicators
used for assessing participant performance throughout
each of the testing sessions. Four individual performance
Larson and Guggenheimer
measures were used to derive VPS scores: success rate,
lateral ball placement, longitudinal ball placement, and
ball velocity. The combined performance on these individual measures provided each participant with a VP
score, ranging between 0-100, with higher scores indicating a better overall forehand groundstroke performance
by the player. The VPS score was then calculated by
taking the average VP score for a particular test session
relative to participant success rate. A VP score was calculated for every ball that successfully landed in the court,
as seen here:
Success rate was defined as a percentage, calculated by taking the total number of forehand drives hit
into the court divided by the total number of attempts
made. Lateral and longitudinal ball placement were determined for each shot and measured as the distance from
the target at which the participant was aiming. Lateral
deviation from the target was measured in a direction
parallel to the baseline, while longitudinal deviation from
the target was measured in the direction parallel to the
singles sideline. Ball velocity was determined by calculating the average lateral and longitudinal speed for each
shot.
Instrumentation and implementation
All tests were conducted using Wilson US Open Junior 25
inch racquets. Each of the participants received their racquets as compensation for participating in the study. The
orange LC balls used in the study were 6.00-6.86cm in
diameter, with a mass between 36.0-46.9g, and a coefficient of restitution ranging between 0.41-0.46 (Wilson,
2010). The SC balls were the standard (Type 2) yellow
balls certified by the ITF for international play (ITF,
2011). The SC balls were 6.54-6.86cm in diameter, with a
mass between 56.0-59.4g, and a coefficient of restitution
ranging between 0.53-0.58 (Wilson, 2010).
The standard court dimensions were 23.8m by
8.2m. The modified orange court dimensions were 18.3m
325
by 5.8m. The net height for both the standard court and
the modified court were 1.07m at the net post and 0.91m
at the center net strap. On each court, targets were placed
on the far corners and on the corners of the service line
and the singles sidelines (Figure 1). Three video camcorders, one Sony Handycam Camcorder DCR-HC52 (Sony
Corporation of America: New York, NY), and two Canon
ZR 960 Camcorders (Canon U.S.A., Inc: Lake Success,
NY), all filming at 60 fields per second and at a shutter
speed of 1/500 of a second, were triangulated on the court
to capture 3D ball placement and the velocity of each
tennis ball (for more details on this setup please see reference Vergauwen et al., 2004). Ariel Performance Analysis
System was used to digitize ball markings through the
process of trimming, digitizing, synchronizing, and transforming data into 3D images; data was filtered at 10Hz.
A calibration cube (91.5 cm) was used to ensure accurate
transformation of the data to 3D, and to scale the ball
landing distances in the computer to corresponding distances on the court.
Procedure
Data was collected on two separate days separated by
24hrs. All participants took part in both days of testing,
the completion order being counterbalanced amongst
participants. On both days of data collection, participants
warmed up with the type of ball they were being tested
with that day; half of them using the LC balls on the
scaled court while the other half used the SC balls on the
standard court. A USPTA certified tennis professional
was used for both sessions and was selected based upon
his 30 years of experience working with children. The
tennis professional was asked to feed the ball to the same
location on the court regardless of the testing condition.
Each rally began with a fed ball from the tennis professional. Participants were given six attempts at three different rally patterns. The rally patterns were as follows:
Pattern 1: four forehand groundstrokes hit deep crosscourt
followed by a fifth forehand hit deep and down-the-line,
Pattern 2: one forehand groundstroke hit deep and downthe-line, Pattern 3:one forehand groundstroke hit sharpangled crosscourt followed by another groundstroke hit
deep and down-the-line. Further details can be found as
described in the ForeGround protocol (Vergauwen et al.,
Figure 1. Court Layout. P1 = participant; Pro = tennis professional; white-dashed-line = pro fed ball; black
triangle = target; back-dashed-arrowed-line = shot recovery distance; black-line = participant’s forehand groundstroke; pictured camera = placement for video camera.
326
Scaling tennis equipment for children
Figure 2. Velocity Precision Success Score. VPS = velocity precision success; SC = standard compression group; LC = low compression group.
2004). The players were instructed to hit as hard as theycould toward a visible target while still maintaining control of the ball. Before each bout of data collection, the
test leader gave the participant a verbal explanation followed by physical demonstration to note which cone was
the target for each rally pattern of the ForeGround protocol (as done in Vergauwen et al., 2004). The explanation
of the pattern was the same regardless of the condition, as
the pattern was the same for all conditions.. The rally
ended when the player either completed the rally pattern
or made an error by hitting the ball into the net or out of
bounds.
Data analysis
The forehand groundstrokes performance scores from this
study were analyzed using SPSS version 18.0 statistical
software. The effect of the independent variable, modified
ball and court, on each of the dependent variables (VPS,
VP, success rate, ball velocity, and ball placement) was
examined using six 2-tailed paired-samples t tests. Confidence intervals were set at 95%.
Results
A 2-tailed paired-samples t test was calculated to compare
the mean VPS scores for both modified and standard
conditions. The mean VPS score for the modified condi-
tion was 2.30 (± 1.17) whereas the mean VPS score for
standard condition was 0.75 (± 0.43). A significant difference was apparent when using ball and court modifications, t(7) = 4.47, p < 0.001. Similarly, a 2-tailed pairedsamples t test was calculated to compare the mean VP
scores for both modified and standard conditions. The
mean VP score for the modified condition was 6.12 (±
2.69) whereas the mean VP score for the standard condition was 3.22 (± 1.74). A significant difference was also
seen in VP scores when using ball and court modifications, t(7) = 3.34, p = 0.01). These data can be seen in
Figures 2 and 3.
Four additional paired-samples t tests were calculated to evaluate the effect of ball and court modification
scaling on success rate, ball velocity, longitudinal ball
placement (Xlong), and lateral ball placement (Zlat). A
significant difference in success rate for the LC condition
was found (t(7) = 8.23, p < 0.001). The ball velocity
during standard conditions was also significantly different
from ball velocity found under modified conditions: (t(7)
= 2.71, p= 0.03). With regards to precision, the participants hit significantly more LC balls closer, Xlong, and Zlat,
to the targets, relative to their SC forehand groundstroke
performance. A significant difference between the two
conditions Xlong was found (t(7) = 3.83, p = 0.01). In the
Zlat direction, a significant difference was evident (t(7) =
3.30, p= 0.01). These data can be seen in Figures 4-7.
Figure 3. Velocity Precision Score. VP = velocity precision; SC = standard compression
group; LC = low compression group.
Larson and Guggenheimer
327
Figure 4. Success Rate. SC = standard compression group; LC = low compression group.
Mean and standard deviation data are displayed in Table
1.
Table 1. Differences in performance between conditions.
Data are means (±SD).
Performance Measure
Standard
Modified
Condition
Condition
0.75 (.43)
2.30 (1.17) *
VPS Score
3.22 (1.74)
6.12 (2.69) *
VP Score
45.0 (17)
58.0 (16.0) *
Success Rate (%)
VP = velocity precision success; VPS = velocity precision success;
* denotes significant difference from standard condition
Discussion
Our primary hypothesis was that children would score
higher on the ForeGround test using modified ball and
modified court conditions when compared to the use of
standard ball and standard court conditions, suggesting
that the modified game enhanced their forehand groundstroke performance. Evidence for this finding is provided
by the significantly greater VPS score under modified
conditions (SC = 0.75, LC = 2.3, p < 0.001). The results
also revealed significant improvements when using ball
and court modifications for all of the other performance
variables as well: VP scores, success rate, velocity, lateral
and longitudinal ball placement.
Several factors may have contributed to the significant enhancement in overall performance for partici-
pants playing under modified conditions; the altered pace
of the game, a smaller court, and a more proportioned
rebound height between the ball and players may have
been contributing factors. Research on adults has shown
that the type of ball used to play tennis alters the pace of
the game, which could logically be extrapolated to children as well (Haake et al., 2000). The LC tennis balls
allow children more time to react to the approaching ball,
thus providing more time to set up their shot. This increased time to react is particularly important for younger
children, as 7 to 8 year olds generally have a difficult time
tracking and making solid contact with the ball (Anderson, 2009).
The results from the present study support the notion that with the use of the LC balls, participants may
have more time to track and set up, therefore providing a
greater window of opportunity to generate solid contact
for their forehand stroke. Considering the enhanced performance found when using the LC balls, the results of
this study suggest that the slower pace of the game due to
the scaling of the ball and court size has an immediate
positive effect on the forehand groundstroke performance
in these children.
A larger court leads to a greater amount of footwork and movement, making it more difficult for young
players to cover the court quickly. A smaller court thus
diminishes the distances players have to travel therefore
increasing their chance of getting into proper position in
Figure 5. Ball Velocity. SC = standard compression group; LC = low compression group.
328
Scaling tennis equipment for children
Figure 6. XlongBall Placement. Xlong= longitudinal direction; SC = standard compression group;
LC = low compression group.
order to execute a quality groundstroke. Considering the
modification in court size that took place in the current
study, it may be that a smaller scaled court is beneficial
for the performance of young players in that it may facilitate more time to prepare the ideal mechanics necessary
for a quality groundstroke. Furthermore, it is known that
proper movement patterns are essential for sound tennis
stroke production (Barrell, 2008), and therefore it is important for children to learn and execute these basic locomotive patterns, as footwork and movement on the
court are foundational elements of a quality tennis stroke
(Elliott et al, 2009). Considering our findings, it is possible that the use of a scaled court was one of several factors that allowed participants more time to set up and
prepare for a quality stroke, thus increasing the likelihood
of getting to the ball, thereby increasing their performance.
The slower LC balls are manufactured to have a
lower coefficient of restitution than SC balls, and consequently they have a lower rebound height (Wilson, 2010).
The rebound height of the LC ball is more proportional to
the child’s height and thus the necessary adjustments to
the rebounding LC ball are minimized as it reaches its
peak within the child’s optimal strike zone. Unlike LC
balls, SC balls peak at a much higher height; children are
therefore forced to adjust their technique, striking the ball
on the rise, or waiting to strike the ball as it descends back
beyond the base line, both of which can hinder the quality
of the executed shot (Barrell, 2008). The results of our
study showed that the use of LC balls enhanced performance, and therefore it is reasonable to assume that the ball
rebound height, when proportional to a player’s height,
may have been a factor contributing to enhanced performance.
The increase in child forehand groundstroke performance due to the LC balls and a scaled court could
have substantial effects on the way tennis is taught to
developing young players that have yet to reach physical
maturity. Considering that success rates were higher for
the LC condition in this study, it is probable that the hitting volume for those practicing with LC balls in the
future would be substantially higher. These findings are
confirmed by the results of Farrow and Reid (2010) who
concluded that scaled-court conditions resulted in a significantly higher volume of forehand groundstroke hitting
for the participants in their study. Since success rate, and
correspondingly hitting volume, typically increases with
the use of LC tennis balls, tennis professionals are able to
implement the game-based approach earlier on in coaching through the use of modified equipment and scaled
courts. In implementing a game-based approach in tennis
lessons, students are able to implicitly learn and practice
skills in the dynamic environment of the game. The LC
balls
and
scaled
court
theoretically
enable
Figure 7. Zlat Ball Placement. Zla t= lateral direction; SC = standard compression group; LC
= low compression group.
Larson and Guggenheimer
children to rally more frequently, thus simulating real
game-based play earlier on in their training. Furthermore,
for children initially learning tennis, practicing with SC
balls on the standard court where they are typically less
successful, could lead to frustration and avoidance of the
sport altogether. Stodden and Goodway (2007) discuss the
importance of developing high motor skill competence,
whether kicking or ball striking, in children in order to
promote physical activity. Utilizing LC balls and a scaled
court, children are likely to have more success, which
may encourage future participation in physical activities
(Fischer et al., 2005; Stodden and Goodway, 2007), including tennis. Therefore, the modification of balls and
courts in tennis may contribute to greater tennis participation and potentially enhance involvement in future physical activity in general.
Participants in the current study were on average
1.2 m laterally and 1.7 m longitudinally closer to the
target when using LC balls. By the very nature of the
ForeGround test, the participant must hit the ball closer to
a target relative to the scaled size (6.5m) of the smaller
court to get the same score as a ball hit farther away from
a target on the standard court (8.2m). Even with the court
being smaller for the LC group, forehand groundstroke
performance measures were superior with LC balls. These
results suggest that children using scaled equipment can
not only hit the ball into the smaller court more often, but
can also do so with greater accuracy.
Our results revealed that the average velocity for
the LC tennis balls was 6.5 km/h faster than the average
velocity of the SC tennis balls. This means that children
were able to hit the LC balls harder despite the smaller
coefficient of restitution of the LC balls. Considering this
finding, it was apparent that there was no trade-off between velocity and precision as might have been expected. For example, low-intermediate level tennis players attempting to hit a tennis ball hard, typically lack
precision at the expense of speed, or vice versa. In the
current study however, performance during the modified
conditions was enhanced as a whole, despite the fact that
it is more difficult for children to execute accurate forehand groundstrokes with court placement while still maintaining control of the power or speed of the ball (Elliott et
al., 2009). Our findings suggest that LC balls not only
enhance children’s ability to hit with more speed, but they
also allow children to execute a more advanced groundstroke, as indicated by enhanced precision and velocity,
while simultaneously increasing success rate. As consistency, speed, and accuracy are fundamentals of tennis
(Bahamonde and Knudson, 2003; Elliott et al., 2009) one
might argue that the enhanced LC performance seen
among children practicing with modified equipment could
have a greater potential to develop tennis fundamentals at
an early age.
The modification system currently evolving in
tennis allows for gradual changes within the court size,
ball type, and racquet size used by children. Children
initially utilizing substantial modifications, starting with
11.0m courts with Stage 3 LC balls, and progress towards
more standardized conditions such as an 18.3m court with
Stage 2 LC balls and the 23.8m court with Stage 1 LC
329
balls, and finally work their way to the use of a SC ball on
the standard 23.8m court (ITF, 2009). The player’s height
and strength determine the appropriate racquet size, which
typically ranges from 58.4 cm to 68.6 cm in length (ITF,
2009). Racquet modifications within the game of tennis
ideally enable young children to perform at a higher level
than they would be capable of performing using standard
equipment, by providing them with equipment that is
proportional to their anthropometric measures. Younger
children are motivated to continue participation in tennis
when skill improvements and playing level progressions
are apparent (Crespo and Reid, 2007). It is thus clearly
important to modify conditions so that children have
success, are intrinsically motivated, and are able to enjoy
the game of tennis. Therefore, increasing children’s exposure to LC tennis balls should be a central focus of children’s programming in the tennis community if it is interested in maximizing the success and growth of young
tennis players.
Despite the above findings, the method of assessment for ball velocity may be considered a limitation of
this study, as the physical differences (mass and diameter)
between the LC ball and the SC ball were not accounted
for. For example the SC ball weighs on average 17.5g
more than the LC tennis ball, which would likely have
had an impact on the resultant mean velocity, which was
not accounted for. It would be advisable that future research take into account the physical differences between
SC and LC balls, such as mass, diameter, and coefficient
of restitution, in order to determine their influence on
corresponding performance variables.
When considering participant selection in an experiment similar to that presently conducted, it is pertinent to consider age, skill level, and participant exposure
to different ball types. Within this study, age and skill
level of the participants were controlled for. Participants
were also selected from a level of programming where
both LC and SC balls were used regularly. Rather than
observing performance, future research focused on the
transfer of learning would be beneficial. However, both
time and resources are needed to examine the transfer of
learning or skill development for both modified and standard equipment; therefore, the practical and logistical
constraints of such a study must first be considered prior
to commencement of data collection. Future studies may
want to consider examining video analysis of the ball
leaving the strings of the racquet so that a qualitative
assessment of skill acquisition maybe done. Such video
analysis may also allow for the quantification of force
being generated off the racquet, while at the same time
providing a more accurate assessment of ball velocity.
Conclusion
Of the minimal research available pertaining to tennis
modifications, results show modest evidence that LC
tennis balls, scaled courts, and scaled equipment influence
how children progress, perform, and learn the game of
tennis (Farrow and Reid, 2010). Of the research available,
most appears to utilize adult participants, suggesting the
need for additional studies on the modification of tennis
330
equipment and the corresponding influence it may have
on the skill development within children. The tennis
community knows that when children develop competency through success early on, they are much more likely
to continue playing and enjoying physical activity (Ryan
et al., 1997). The participants of this study were found to
have enhanced forehand groundstroke performance when
using modified balls and court versus standard balls and
court; considering these finding one might suggest that
children may have enjoyed the game to a greater extent
due to their enhanced success. As stated in the literature,
modified equipment can have a significant impact on the
performance and enjoyment of young tennis players.
Therefore, modifying the game of tennis may play a vital
role in future tennis instruction and the continued enjoyment of young tennis enthusiasts around the world.
Acknowledgments
Choice Health and Fitness: for sharing their facility, tennis professionals, and athletes. Mike Orr and Tim Wynne for their technical assistance.
We would like to acknowledge the International Tennis Federation
researchers, especially, James Newman for his methodological contributions. Chris Kushner, Global Business Manager Tennis Balls, Mike
Haber, Territory Manager, and Erika Offerdahl, USTA Promotions
Manager from Wilson Sporting Goods Co. for donating low compression tennis balls and racquets.
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Key points
• This study observed the effects of modified tennis
balls and court had on the forehand groundstroke
performance in children.
• Modified ball compression and modified court size
can increase control, velocity and overall success of
tennis performance.
• Children will have more success learning the game
of tennis using modified equipment than using standard equipment.
AUTHORS BIOGRAPHY
Emma J. LARSON
Employment
Choice Health and Fitness, Tennis Professional, Grand Forks, ND.
Degree
MSc
Research interests
Determinants of tennis performance in children.
E-mail: [email protected]
Larson and Guggenheimer
Joshua D. GUGGENHEIMER
Employment
Assistant Professor, Department of Physical
Education, Exercise Science and Wellness,
University of North Dakota.
Degree
PhD
Research interests
Exercise protocols employed by older adults
to aid in fall prevention. The impact of whole
body vibration on balance, performance, and
other health parameters. Enhancement of
sport performance through specific preconditioning activities.
E-mail:
[email protected]
Emma J. Larson
Choice Health and Fitness, Att: Tennis Office, 4401 South 11th
Street , Grand Forks, ND 58208-2429, USA
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